During the summer of 2002, western North America experienced one of the largest forest fires in recorded history. The Biscuit Fire burned nearly one half million acres of mostly pristine habitats in Oregon and California. This project will exploit the mosaic of replicated burned and unburned sites left by this fire, and apply an experimental approach to address general questions in community ecology. Because the P.I.s had collected pre-burn data on the structure of the plant and ant communities in this area, they are in a unique position to follow trajectories of community re-assembly compared to initial conditions. At replicated sites they will erect barriers to exclude ants, a major seed dispersal agent, and test for effects on rates and trajectories of plant community assembly, especially in isolated fens. This work will significantly extend our knowledge on ant-plant community interactions and re-assembly after catastrophic fire.